In-mold non-time dependent determination of injection molded part ejection readiness
Non-time dependent measured variables are used to effectively determine an optimal ejection time of a part from a mold cavity. A system and/or approach may first measure at least one non-time dependent variable during an injection molding cycle. The part is ready to be ejected from the mold upon the measured variable reaching a threshold value indicative of, for example, a part temperature dropping below an activation temperature.
1. A method for determining whether a part is ready to be ejected from a mold cavity during an injection molding cycle, the method comprising:
measuring at least one non-time dependent variable during the injection molding cycle;
upon the measured at least one non-time dependent variable reaching a threshold value indicative of the part being structurally sound, ejecting the part from the mold cavity;
wherein the at least one non-time dependent variable comprises at least one of a Shore D Durometer or a Rockwell R hardness value measured via a hardness sensor.
2. The method of claim 1 , wherein the at least one non-time dependent variable is measured at a location inside of the mold cavity.
3. The method of claim 1 , wherein the at least one non-time dependent variable is measured at a location outside of the mold cavity.
4. The method of claim 1 , further comprising, in a subsequent injection molding cycle, using the measured variable from the previous injection molding cycle to determine when the part is structurally sound for ejection from the mold cavity.
5. A method for determining whether an injection molded part is ready to be ejected from an injection mold cavity, the method comprising:
measuring one or more non-time dependent variables at a location outside of the mold cavity, wherein the at least one non-time dependent variable comprises at least one of a Shore D Durometer or a Rockwell R hardness value measured via a hardness sensor;
upon the measured one or more non-time dependent variables reaching a threshold value indicative of the part being structurally sound, ejecting the part from the mold cavity.
6. The method of claim 5 , further comprising, in a subsequent injection molding cycle, using the measured variable from the previous injection molding cycle to determine when the part is structurally sound for ejection from the mold cavity.
7. A method for determining whether an injection molded part is ready to be ejected from an injection mold cavity, the method comprising: in a first injection molding cycle, injecting a first shot of molten plastic material into a mold cavity; during the first injection molding cycle, measuring a first non-time dependent variable value of a non-time dependent variable, the first non-time dependent variable value being indicative of a part being structurally sound; during a second injection molding cycle subsequent to the first injection molding cycle, injecting a second shot of molten plastic material into the mold cavity; during the second injection molding cycle, measuring a second non-time dependent variable value of the non-time dependent variable; and ejecting the part from the mold cavity when the second non-time dependent variable value is approximately equal to the first non-time dependent variable value; wherein the non-time dependent variable comprises at least one of a shore D Durometer or a Rockwell R hardness value measured via a hardness sensor.
8. The method of claim 7 , wherein the first non-time dependent variable value is measured prior to ejecting the part from the mold cavity.
9. The method of claim 7 , wherein the first non-time dependent variable value is measured after the part produced during the first injection molding cycle is ejected from the mold cavity.